The Monetary Authority of Singapore (MAS) has banned former high-flying Goldman Sachs banker Tim Leissner from trading in the country, effective today.

In a statement today, MAS issued the 10-year prohibition order against Leissner for 1MDB-related breaches.

According to MAS, Leissner had in June 2015 issued an unauthorised letter to a financial institution in Luxembourg and made false statements on behalf of Goldman Sachs (Asia) without the firm's knowledge.

Effectively, Leissner has been barred from performing any activity regulated by Singapore's Securities and Futures Act or participating in the management of any market services firm in Singapore.

Leissner was reportedly a key figure in Goldman Sach's effort in raising US$6.5 billion through the sale of three bonds in 2012 and 2013.